Magnitude and Frequency in Proglacial Rivers
Title | Magnitude and Frequency in Proglacial Rivers PDF eBook |
Author | Philip M. Marren |
Publisher | |
Pages | 49 |
Release | 2005 |
Genre | Geomorphology |
ISBN |
Proglacial fluvial sedimentary systems receive water from a variety of sources and have variable discharges with a range of magnitudes and frequencies. Little attention has been paid to how these various magnitude and frequency regimes interact to produce a distinctive sedimentary record in modern and ancient proglacial environments. This paper reviews the concept of magnitude and frequency in relation to proglacial fluvial systems from a geomorphic and sedimentary perspective rather than a hydrological or statistical perspective. The nature of the meltwater inputs can be characterised as low-magnitude-high-frequency, primarily controlled by ablation inputs from the source glacier, or high-magnitude-low-frequency, primarily controlled by "exceptional" inputs. The most important high-magnitude-low-frequency inputs are catastrophic outburst floods, often referred to by the term jokulhlaup (Icelandic for glacier-burst). Glacier surges are an additional form of cyclical variation impacting the proglacial environment, which briefly alter the volumes and patterns of meltwater input. The sedimentary consequences of low-magnitude-high-frequency discharges are related to frequent variations in stage, the greater directional variability that sediment will record, and the increased significance of channel confluence sedimentation. In contrast, the most significant characteristics of high-magnitude-low-frequency flooding include the presence of large flood bars and mid-channel "jokulhlaup" bars, hyperconcentrated flows, large gravel dunes, and the formation of ice-block kettle hole structures and rip-up clasts. Glacier surges result in a redistribution of low-magnitude-high-frequency processes and products across the glacier margin, and small floods may occur at the surge termination. Criteria for distinguishing magnitude and frequency regimes in the proglacial environment are identified based on these major characteristics. Studies of Quaternary proglacial fluvial sediments are used to determine how the interaction of the various magnitude and frequency regimes might produce a distinctive sedimentary record. Consideration of sandur architecture and stratigraphy shows that the main controls on the sedimentary record of proglacial regions are the discharge magnitude and frequency regime, sediment supply, the pattern of glacier advance or retreat, and proglacial topography. A model of sandur development is suggested, which shows how discharge magnitude and frequency, in combination with sandur incision and aggradation (controlled by glacier advance and retreat) can control sandur stratigraphy.
Magnitude and Frequency Regimes of Proglacial Rivers in Eastern Scotland During the Late Devensian
Title | Magnitude and Frequency Regimes of Proglacial Rivers in Eastern Scotland During the Late Devensian PDF eBook |
Author | Philip M. Marren |
Publisher | |
Pages | |
Release | 2000 |
Genre | |
ISBN |
Geomorphology of Proglacial Systems
Title | Geomorphology of Proglacial Systems PDF eBook |
Author | Tobias Heckmann |
Publisher | Springer |
Pages | 352 |
Release | 2018-11-29 |
Genre | Science |
ISBN | 3319941844 |
This book discusses the recession of alpine glaciers since the end of the Little Ice Age (LIA), which has been accelerating in the past decades. It provides an overview of the research in the field, presenting definitions and information about the different proglacial areas and systems. A number of case studies are from the PROSA project group which encompasses the expertise of geomorphologists, geologists, glaciologists and geodesists. The PROSA joint project (High-resolution measurements of morphodynamics in rapidly changing PROglacial Systems of the Alps) is determined to tackle the problems of geomorphic activity on sediment export through a quantification of sediment fluxes effected by the aforementioned geomorphic processes within the forefield of the Gepatschferner glacier (Central Alps, Austria).
River Magnitude and Frequency in the United States
Title | River Magnitude and Frequency in the United States PDF eBook |
Author | LASSALINE D M |
Publisher | |
Pages | 324 |
Release | 1967 |
Genre | Rivers |
ISBN |
The Structure, Function and Management Implications of Fluvial Sedimentary Systems
Title | The Structure, Function and Management Implications of Fluvial Sedimentary Systems PDF eBook |
Author | Fiona J. Dyer |
Publisher | |
Pages | 502 |
Release | 2002 |
Genre | Rivers |
ISBN | 9781901502961 |
Gravel Bed Rivers
Title | Gravel Bed Rivers PDF eBook |
Author | Michael Church |
Publisher | John Wiley & Sons |
Pages | 605 |
Release | 2012-01-30 |
Genre | Nature |
ISBN | 0470688904 |
Gravel-Bed Rivers: Processes, Tools, Environments presents a definitive review of current knowledge of gravel-bed rivers, derived from the 7th International Gravel-bed Rivers Workshop, the 5-yearly meeting of the world’s leading authorities in the field. Each chapter in the book has been specifically commissioned to represent areas in which recent progress has been made in the field. The topics covered also represent a coherent progression through the principal areas of the subject (hydraulics; sediment transport; river morphology; tools and methods; applications of science). Definitive review of the current knowledge of gravel-bed rivers Coverage of both fundamental and applied topics Edited by leading academics with contributions from key researchers Thoroughly edited for quality and consistency to provide coherent and logical progression through the principal areas of the subject.
Megaflooding on Earth and Mars
Title | Megaflooding on Earth and Mars PDF eBook |
Author | Devon M. Burr |
Publisher | Cambridge University Press |
Pages | 330 |
Release | 2009-09-24 |
Genre | Science |
ISBN | 0521868521 |
A research summary of the causes and effects of megaflooding on Earth and Mars, for hydrologists, planetary scientists and engineers.